Optimal bus fleet management strategies in a congested road network

International Conference on Advanced Systems for Public TransportTHE 11th International Conference on Advanced Systems for Public Transport is jointly organized by Hong Kong Society for Transportation Studies and Department of Civil and Environmental Engineering, The Hong Kong University of Science and TechnologyA simulation model of car, bus and bus passengers that takes into account the effects of carbus interactions, bus stop dwell time and bus fleet size constraints on bus system performance is described. Feedback loops are incorporated within the model to ensure consistency in car driver and bus passenger route choice behaviors and bus stop dwell time assumptions. A hypothetical network is provided to demonstrate the feasibility of using this model to evaluate alternative bus fleet management strategies.published_or_final_versio

Influence of real-time information provision to vacant taxi drivers on taxi system performance

This paper assumes that all taxi drivers adopt a profit maximization strategy when searching for customers. Some taxi drivers are provided with real-time information on customer and taxi queue lengths at all taxi stands while others have no information at all. The questions to be investigated are: (1) will equipped taxi drivers earn a higher profit compared to the uninformed taxi drivers? (2) What is the impact of real-time information provision to a portion of all the taxi drivers on the overall taxi system performance? To find answers to these questions, a case study is conducted by assuming a hypothetical linear city with a single city centre, ten taxi stands and twenty residential zones. A discrete-event dynamic simulation model is adopted to simulate the movements of taxis and to estimate various taxi system performance characteristics, such as taxi operation profit and customer waiting time. The time period simulated is a 3-hour morning commune. The taxi fleet size, fare structure, taxi operation cost and customer demand pattern are all assumed given. The simulation model is used to investigate the variation of taxi system performance with the proportion of informed taxi drivers in the taxi fleet.published_or_final_versionThe 12th World Conference of Transport Research (WCTR 2010), Lisbon, Portugal, 11-15 July 2010

Determination of optimal successor function in phase-based control using neural network

A phase-based method for fixed-time signal control of traffic improves significantly the junction performance over conventional stage-based method of control due to the higher flexibility in specification of signal timings, where the control variables comprise the start and duration of green phases and the cycle time at which the junction is operated. The cycle-structure is specified by a successor function, a combination of 0 and 1 for all incompatible pairs of phases, which indicates the order of phases in a cycle. Normal procedure optimises the timings for each of these successor functions to determine the best timing plan. The computing time is found to be approximately proportional the number of such functions. To reduce the computational requirement, and hence enhance its applicability to real-time actuated control, a neural network is employed in this paper to help identify the optimal successor function for further optimization of timings. Encouraging results are obtained.published_or_final_versio

Accounting Profession in South Korea; Professional Accounting in Foreign Country Series

https://egrove.olemiss.edu/aicpa_guides/1694/thumbnail.jp

The Hong Kong second parking demand study

This paper describes the background, objectives, surveys, models, findings and recommendations of the Hong Kong second parking demand study. This study aims to give strategic directions to guide the planning and management of parking facilities in Hong Kong. It comprises extensive surveys to determine the parking inventory, parking characteristics and driver behaviour. Demand models were developed to predict the future night-time and daytime parking demand over a planning horizon of 15 years. All types of vehicle, including private cars, taxis, motorcycles, coaches and goods vehicles, were included in the analysis. The recommendations of a previous parking demand study have been reviewed, and new recommendations are given.published_or_final_versio

Development of a transport model for East Kowloon, Hong Kong

After the relocation of the airport, much land-use change and redevelopment is expected in the East Kowloon District in the city of Hong Kong. Consequently, a comprehensive review of the land-use and transportation plans for the district was required. In the study, a sub-regional transport model for the district was developed. This model was used to forecast the vehicular, public transport and pedestrian demands arising from land-use and transportation system changes in and around the district. This paper describes the modelling approach and validation results. | After the relocation of the airport, much land-use change and redevelopment is expected in the East Kowloon District in the city of Hong Kong. Consequently, a comprehensive review of the land-use and transportation plans for the district was required. In the study, a sub-regional transport model for the district was developed. This model was used to forecast the vehicular, public transport and pedestrian demands arising from land-use and transportation system changes in and around the district. This paper describes the modelling approach and validation results.published_or_final_versio

The Hong Kong parking demand study

This paper describes the objectives, methodology, findings, recommendations and implementation programme of a parking demand study which was conducted in Hong Kong during the period 1993-1995. The study comprises extensive surveys to establish parking characteristics and parking inventory, a stated preference survey to estimate the influence of parking space availability on modal choice, development of parking demand models for private cars and goods vehicles, identification of problems related to parking, and formulation of remedial measures.published_or_final_versio

Advancement of the annual traffic census in Hong Kong

This paper summarises the process, findings and recommendations of a recently completed joint university consultancy project that reviewed the annual traffic census (ATC) in Hong Kong. The results of a survey that assessed the usefulness of the census report are presented, together with an overview of the existing traffic data collection process and traffic detection equipment. Areas for improvement are then identified, including the sampling strategies for the collection of vehicle classification and occupancy data, the procedure for the development of group scaling factors, the method for the selection of core and coverage stations, the approaches to developing growth factors and traffic flow estimation, the presentation method and database structure of the census framework, and the manpower requirements. Based on these identified areas, a new computer program is developed to integrate all of the tasks of the census report and to produce the results in CD-ROM format. Finally, concluding remarks are given together with recommendations for further study.published_or_final_versio

Cycling comfort on asphalt pavement: Influence of the pavement-tyre interface on vibration

Attainment of cycling comfort on urban roads encourages travelers to use bicycles more often, which has social and environment benefits such as to reduce congestion, air pollution and carbon emissions. Cycling vibration is responsible for the cyclists’ perception of (dis)comfort. How asphalt pavement's surface characteristics relate to cycling comfort, however, remains undiscovered. In this study, the cycling vibration intensity on 46 sections of 24 urban roads was tested using a dynamic cycling comfort measure system while the cyclists’ perception of vibration was identified via questionnaires; the cycling comfort was then defined based on the cycling vibration. To record the accurate pavement-tyre interface under a stable environment, a total of 19 pavement sections were scanned using a 3D digital camera. These 3D models were then 3D printed, which are used to conduct the pressure film test using a self-developed pavement-tyre interface test system. Three ranges of pressure films were adopted to characterize the pavement-tyre interface via 9 parameters, namely contact area (A c ), unit bearing area (B u ), stress intensity (S i ), stress uniformity (S u ), kurtosis (S ku ), spacing (Sp a ), maximum peak spacing (Sp max ), radius ratio (R r ) and fractal dimension (F d ), in consideration of the area characteristics, pressure amplitude, peak spacing and shape of the interface. Finally, the significant interface parameters were identified, and the regression model between interface parameters and cycling comfort was established. Results show that the cycling vibration was described to be ‘very comfortable’ when the human exposure to vibration level (a wv ) was less than 1.78 m/s 2 ; ‘comfortable’ when the a wv was between 1.78 m/s 2 and 2.20 m/s 2 ; and ‘uncomfortable’ when the a wv was greater than 2.20 m/s 2 . The average stress on rear wheel-pavement interface is higher than that of the front wheel. B u-0.6 , Sp a-0.6 , and F d-0.6 are significant to cycling vibration. The 2LW pressure film is recommended for use to measure the bicycle pavement-tyre interface. The recommended interface characteristics are less than 7 mm 2 of the unit bearing area, 6 mm of average spacing and 2.38 of fractal dimension. Finally, dense asphalt mixture performs better in providing cycling comfort than the gap-graded asphalt mixture. Results of this study contribute to current knowledge on bike lane comfort and pavement design, the findings should be interested in cyclists, transport planners, and road authorities

The Spatial Origin of a Perceptual Transition in Binocular Rivalry

When the left and the right eye are simultaneously presented with incompatible images at overlapping retinal locations, an observer typically reports perceiving only one of the two images at a time. This phenomenon is called binocular rivalry. Perception during binocular rivalry is not stable; one of the images is perceptually dominant for a certain duration (typically in the order of a few seconds) after which perception switches towards the other image. This alternation between perceptual dominance and suppression will continue for as long the images are presented. A characteristic of binocular rivalry is that a perceptual transition from one image to the other generally occurs in a gradual manner: the image that was temporarily suppressed will regain perceptual dominance at isolated locations within the perceived image, after which its visibility spreads throughout the whole image. These gradual transitions from perceptual suppression to perceptual dominance have been labeled as traveling waves of perceptual dominance. In this study we investigate whether stimulus parameters affect the location at which a traveling wave starts. We varied the contrast, spatial frequency or motion speed in one of the rivaling images, while keeping the same parameter constant in the other image. We used a flash-suppression paradigm to force one of the rival images into perceptual suppression. Observers waited until the suppressed image became perceptually dominant again, and indicated the position at which this breakthrough from suppression occurred. Our results show that the starting point of a traveling wave during binocular rivalry is highly dependent on local stimulus parameters. More specifically, a traveling wave most likely started at the location where the contrast of the suppressed image was higher than that of the dominant one, the spatial frequency of the suppressed image was lower than that of the dominant one, and the motion speed of the suppressed image was higher than that of the dominant one. We suggest that a breakthrough from suppression to dominance occurs at the location where salience (the degree to which a stimulus element stands out relative to neighboring elements) of the suppressed image is higher than that of the dominant one. Our results further show that stimulus parameters affecting the temporal dynamics during continuous viewing of rival images described in other studies, also affect the spatial origin of traveling waves during binocular rivalry